Human perspiration is initially odorless but upon standing develops an unpleasant odor which is due almost entirely to bacterial decomposition of the perspiration. Cosmetic compositions designed to treat perspiration odor act either by inhibiting the flow of perspiration from the skin, or by eliminating only the odor associated with perspiration.
Antiperspirants inhibit perspiration flow because they contain metal salts which have astringent properties. Deodorants, on the other hand, do not alter the volume of perspiration secreted. Since most body odor is the result of bacterial action on perspiration, deodorants contain certain agents such as phenolic derivatives, quaternary ammonium compounds, hexachlorophene, and various ion exchange resins, all of which possess effective antibacterial action.
Today, many different types of deodorants are available. However, clear deodorant preparations are extremely popular because consumers associate clarity with cleanliness and effectiveness. It is particularly difficult to make clear deodorant sticks which have the stability required for commercial use. In many instances the clear stick products are tacky and long drying which causes the underarm to feel wet and sticky after the stick is applied. In addition, these sticks have poor stability, often will turn cloudy within days or months, which makes them unsuitable for commercial use.
Cosmetic compositions in stick form are well known. For example, U.S. Pat. No. 4,759,924 (Luebbe) discloses a transparent soap gel stick useful for deodorant purposes.
U.S. Pat. No. 4,816,261 also teaches clear deodorant sticks which contain the gelling agent dibenzylidene sorbitol monoacetal rather than soap.
U.S. Pat. No. 5,128,123 discloses a clear cosmetic stick which essentially contains an alkyoxylate copolymer.
U.S. Pat. No. 5,120,541 discloses transparent sticks containing monohydric alcohols and a soap crystal growth inhibitor.
U.S. Pat. No. 4,617,285 discloses a stick composition essentially containing diisopropyl adipate.
U.S. Pat. Nos. 4,504,465, 4,226,889, 4,702,916, and 4,732,754 also disclose cosmetic gel stick compositions containing soap.
None of the above references disclose the particular clear deodorant stick compositions of the invention.
The object of the invention is to develop a clear deodorant stick with improved clarity and stability.
Another object of the invention is to develop a clear deodorant stick which does not contain the benzylidene sorbitol gelling agents or monohydric alcohols.